cant see my site in browser

Hi

I am new to ASP.Net.I have created a file system based web application.I tried to view it in browser.I can do so when i do http://localhost:portno/project name.However I cannot view it when i do http://computername:portno/project name.I cant unserstand where the problem is.I have placed the project inside wwwroot and have webshared it well.I have allowed it in network sharing too.Another thing that is confusing me is when i dont give the port no that is http://computer name/project name  it shows me the directory listing of the project .But when i click on any of the aspx page,the following error is shown in the browser:


"The XML page cannot be displayed
Cannot view XML input using XSL style sheet. Please correct the error and then click the Refresh button, or try again later.

A name was started with an invalid character. Error processing resource 'http://jeri/joint/Default.aspx'. Line 1, Position...

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
-^"


I am using IIS version 5 and framework 2.

Please help! I know very little about IIS settings and all.Thanks in advance!!